In computer systems, an information object such as a file stores information (also referred to as content) in a particular format that is accessible by invoking a native application capable of reading and processing that format. For example, documents in different formats are accessible via different word processing applications. To access information objects via conventional graphical user interfaces (GUIs), users typically locate the information object and invoke an application capable of providing access to the information.
Many conventional graphical user interfaces organize and display information objects hierarchically in file systems comprising directories (e.g. folders) and files at one or more levels. To access a particular information object, users must selectively traverse through the file system by repeatedly selecting a series of nested directories by clicking on directory icons to access a lower level directory containing the information object. The hierarchy of a conventional file system is typically created manually by the user by creating the nested, hierarchical arrangement of directories and moving the information object into one of these directories. This process of manually organizing objects requires the user to invest considerable time and attention in deciding on which directories and subdirectories to create, and where to place information objects within them. In addition, once created, the hierarchical directory structure is entirely static, and does not change unless the user purposely creates, deletes, or reorganize the contents.
Hierarchical organization of information objects in conventional GUIs also suffers from a tradeoff between focus and context. While viewing a hierarchical directory structure, users have access to the context of an information object, such as the location of the object in a hierarchical file system, but they are unable to access the detailed information in a particular object. On the other hand, while accessing the detailed information in a particular object, for example while viewing a video file, users are likely to lose context of where the information is in a hierarchy or in an overall information schema. This loss of context while accessing the content of an information object can inhibit understanding of the content and can make it difficult for a user to find logically related information. One example of a hierarchical file system that suffers from a tradeoff between context and focus is Windows Explorer provided by the Microsoft Corporation.
In conventional graphical user interfaces such as the Windows operating system, the icon or symbol associated with an information object provides only limited information about the file or folder, typically only the name and type of information object and the associated application for accessing the object. For example, a Microsoft Word document has an icon resembling a sheet of paper. Unless a user already knows the contents of an information object, the information object's icon provides no additional information about the content of the information object to the user to facilitate a decision as to whether or not to access the object.
Conventional graphical user interfaces also allow users to search for information that meets specified parameters. For example, Windows Explorer allows users to search for particular file names, file attributes (e.g., type, modification date), or the contents of a file (e.g., words contained therein). However, such search mechanisms require users to generate queries to retrieve relevant information, that is, to know that they are looking for something in particular at a given time. Further, a set of information objects retrieved by a query are not organized to facilitate navigation by a user based on logical relationships between the content of the objects.
Conventional techniques for rendering graphics include mipmapping. Mipmaps are pre-calculated, optimized collections of bitmap images. Bitmap images in a mipmap are different resolution versions of a single underlying image or texture map. When a user zooms in to a graphic, increasingly higher resolution ones of the images are displayed; as the user zooms out, increasingly lower resolution ones of the images are displayed. In mipmapping, the low resolution images are simply downconverted versions of one or more of the high resolution images. Thus, at best, mipmapping changes the pixel resolution of a displayed image based on a current zoom level. Conventional mipmapping techniques are unable to present different content, different types of information objects, and/or information objects from different sources in response to a current zoom level.